Basic principalsThe art or process of wire drawing like the name implies is to draw a wire of a bigger diameter through a hole with smaller diameter hereby reducing the diameter through plastic deformation while the volume remains the same.

Sunday, May 16, 2010

The other code breaking electronic machines in the Newmanry.

Various cryptographic problems required the building of specialist machines.

There was still the need for multiple paper tape comparison, so Heath Robinson evolved into Old Robinson, the first upgrade, then to Super Robinson. The ultimate multi tape machine was Mrs Miles. It had four tape readers and its name derived from a contemporary lady who had quadruplets.

There was also a proposal for a combined Robinson and Colossus, called Robinson and Cleaver, but it is not clear whether this was ever built.

More important were the Dragon series. These were designed to "drag" a series of characters along a cipher text, (usually a DeChi), looking for significant match points. The ultimate machine of this type was Aquarius. This used voltage storage on a large bank of capacitors to hold patterns of bits for testing matches against cipher or DeChi streams. (The capacitor voltages had to be continuously refreshed, hence Aquarius).

A completely different machine was the 5202 photographic system this did not become operational until 1945. It worked by comparing optically film of cipher text against expected Lorenz patterns. The Newmanry report says that it was successful against a narrow range of problems but was not as flexible as Colossus.

The Testery and Newmanry contribution to the War effort

The contribution to D-Day

Colossus reduced the time to break Lorenz messages from weeks to hours. In January 1944 it was just in time for the deciphering of messages which gave vital information to Eisenhower and Montgomery prior to D-Day, 6th June 1944. These deciphered Lorenz messages showed that Hitler had swallowed the deception campaigns, the phantom army in the South of England, the phantom convoys moving east along the channel; that Hitler was convinced that the attacks were coming across the Pas de Calais and that he was keeping Panzer divisions in Belgium.

After D-Day the French Resistance and the British and American Air Forces bombed and strafed all the telephone and teleprinter land lines in Northern France, forced the Germans to use radio communications and suddenly the volume of intercepted messages went up enormously. Here are some of the German radio links using Lorenz, which were intercepted and broken. They all had FISH names, like JELLYFISH, the German High Command link from Berlin to Western Europe Command.

The Mark 1 had been rapidly augmented by the Mark 2 Colossus in June 1944 and eight more were quickly built to handle the increase in messages. The Mark 1 was upgraded to a Mark 2 and there were thus ten Mark 2 Colossi in the Park by the end of the war. By the end of hostilities, 63 million characters of high grade German messages had been decrypted — an absolutely staggering output from just 550 people at Bletchley Park, plus of course the considerable number of interceptors at Knockholt, with backups at Shaftesbury and Coupar in Scotland.